Outside the national guard base in Mariupol, an officer pointed out the cartridge cases on the ground.

Nearby, a small boy pretended to drive a smashed-up police car, to the delight of the photographers gathered around.

Among them, two investigators were patiently attempting to map out the scene, as journalists tramped through their chalk marks.

Ukraine's acting interior minister says all this was the work of pro-Russian separatists.

A uniformed officer told us he couldn't say who they were, but the base was attacked by a crowd of men - some in sportswear, some in combat fatigues - with automatic weapons, handguns and Molotov cocktails.

He said they had fought back, that the troops inside remained loyal to Kiev.

But ultimately, what actually happened here may turn out to be less important than what people believe happened here - and different people here have heard different, wildly divergent versions of events.

One lady told us she had seen everything - that men with western Ukrainian accents, quite possibly members of the right-wing militant group Right Sector - had provoked the whole thing.

Another man told us those inside the base fired first, albeit into the air, and the protesters had responded with Molotov cocktails.

Video:Pro-Russia Separatists Attack Base

Two men shouted each other down in the street: one pro-Ukrainian, criticising the way the pro-Russian protesters behave; the other called him a provocateur, and said they were protecting them from the junta in Kiev.

An older couple drove up with supplies of food for the troops.

The woman, who told us she was 74, said she wanted to show her support for them, and that Russia had brought war to her country.

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"I want peace, love and unity," she said.

Nearby, we found a man pushing his granddaughter on a swing. He said his daughter had phoned him last night to say she could hear gunfire. He told her to lie on the floor.

We asked him what he wants, whether he is for Russia or Ukraine, whether he supports the actions of the protesters.

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"What I want is as every normal person in the south-east of Ukraine wants," he said.

"That our opinion should be heard by the government, and that we should have a normal life."